Speaker 1: There is one other thing. I'm including it here is
Speaker 1: an epilogue because the series is over, its message has
Speaker 1: been sent. But this other thing does tie into existential
Speaker 1: risks in some pretty interesting ways, so I wanted to
Speaker 1: include it. I'll just leave it here and you can
Speaker 1: decide how you feel about it. Back in two thousand three,
Speaker 1: Nick Bostrom expanded on a concept that had been around
Speaker 1: at least since the classical Greeks first recorded their thoughts
Speaker 1: on it, the idea that what we experience as reality
Speaker 1: isn't real the followers of Plato discussed in the Academy
Speaker 1: at Athens, and then in the sixteen hundreds it was
Speaker 1: taken up and examined by Renee Descartes, the Enlightenment philosopher
Speaker 1: who famously identified that he was because he thought. Descartes
Speaker 1: wondered if perhaps we exist in a reality that's actually
Speaker 1: a dream. After considering his own experience with dreams, Descartes
Speaker 1: decided that if we do exist in a dream, we
Speaker 1: would never be able to tell. What he experienced in
Speaker 1: dreams seemed like reality to him just as much as
Speaker 1: reality did in waking life. Without any indication to distinguish
Speaker 1: between the two, we would never really be able to
Speaker 1: tell the difference. It wasn't until two thousand three, however,
Speaker 1: when Nick Bostrom wrote his paper entitled Are You Living
Speaker 1: in a Computer Simulation? That anyone went to the trouble
Speaker 1: of formalizing the idea that what we consider reality is
Speaker 1: an actually basement reality. Bostrom hit upon a way to
Speaker 1: examine the nature of reality, and it's based on whether
Speaker 1: we expect to make it through the great filter. He
Speaker 1: called it the simulation argument, which supposes that there's a
Speaker 1: very good chance and we are not actually real life humans,
Speaker 1: that instead we are simulated humans living in a simulated universe.
Speaker 1: So Nick Bolstrom refined this into a proper logical argument
Speaker 1: to show that you need to kind of accept that
Speaker 1: either we are going to go extinct really soon, or
Speaker 1: where for some reason, our post human descember will never
Speaker 1: ever run simulations, maybe because very impossible, or because they're
Speaker 1: very very moral or have some coordination, or we are
Speaker 1: almost certainly in a simulation. If you didn't recognize that voice,
Speaker 1: that was Ander Sandberg, Bostrom's colleague at the Future of
Speaker 1: Humanity Institute. Being an argument, the simulation argument doesn't provide
Speaker 1: evidence one way or the other, which is beautiful because
Speaker 1: that leads it to each person to be persuaded by
Speaker 1: it or not. But to get into it, we first
Speaker 1: have to agree on a couple of points. Remember when
Speaker 1: humanities cosmic endowment came up all the way back in
Speaker 1: episode three. That's the idea that if we are the
Speaker 1: only intelligent life in the universe, as it seems we are,
Speaker 1: then once we spread off of Earth, all the matter
Speaker 1: and energy that we can get our hands on before
Speaker 1: it expands out of our reach forever is ours to
Speaker 1: put to use for whatever amazing things we can come
Speaker 1: up with. If we managed to successfully navigate the existential
Speaker 1: risks that are coming our way and pass through the
Speaker 1: great Filter, then it seems likely that our descendants humans
Speaker 1: in the future will use some of that cosmic endowment
Speaker 1: to create massive computers. Perhaps we will use nanobots to
Speaker 1: deconstruct planets to use as raw materials for those massive computers,
Speaker 1: and we'll build Dyson's feares to capture energy at the
Speaker 1: source of a star to power them. That our descendants
Speaker 1: will have massive computers seems like a fairly tame prediction
Speaker 1: as far as predictions about the future go. Think about
Speaker 1: how important computing is to our civilization today. It's a
Speaker 1: pretty good bet that as we continue moving along our
Speaker 1: technological path, computing will grow ever more important, and should
Speaker 1: we end up a post biological society, computers will become
Speaker 1: even more important. They will provide the support structure for
Speaker 1: our very being. So if we're agreed that if we
Speaker 1: managed to save the world, are descendants will go on
Speaker 1: to have vast amounts of computation available to them, we
Speaker 1: can move on to the next point that they will
Speaker 1: use some of that computing power to run simulations of
Speaker 1: us their ancestors. They could have any reason to run
Speaker 1: simulations of human history for fun, like the reason we
Speaker 1: play the sims or Age of Empires as a sociological
Speaker 1: or anthropological model, or as part of an educational exhibit
Speaker 1: that celebrates the time that we save the future of
Speaker 1: the entire human race and intelligent life in the universe
Speaker 1: from near extinction. Whatever their reason, we can imagine that
Speaker 1: in the future they might run what Bostrom calls ancestor simulations. Importantly,
Speaker 1: one the beautiful things that makes the simulation argument persuasive
Speaker 1: is that it doesn't matter when this will happen. The
Speaker 1: argument puts no time constraints on any of this. Our
Speaker 1: descendants can build those computers and run those simulations a
Speaker 1: thousand years from now or a million. It doesn't matter,
Speaker 1: just so long as we can agree that at some
Speaker 1: point they will. So if we're agreed that our descendants
Speaker 1: will at some point in the future build massive computers
Speaker 1: and use some of that ridiculous amount of computing power
Speaker 1: available to them to run simulations of human history, we
Speaker 1: can now enter the simulation argument. It goes something like this,
Speaker 1: Either we are living in a computer simulation run by
Speaker 1: our descendants in the future, or we're not. If we're
Speaker 1: not living in a simulation, then that means we are
Speaker 1: what we tend to think. We are members of the
Speaker 1: real life human race, living in basement or real reality
Speaker 1: in the twenty first century, about three and a half
Speaker 1: billion years on from the origin of life on Earth.
Speaker 1: But as plainly obvious as that may seem, the simulation
Speaker 1: argument raises a question why aren't we simulated? Bostrom identified
Speaker 1: a couple of possible reasons. One is that our descendants
Speaker 1: are fully capable of simulating us, they just choose not to.
Speaker 1: It's possible that our ancestors won't run simulations because they're
Speaker 1: computing power is far too precious for even a minute
Speaker 1: fraction of it to be allocated to something potentially frivolous
Speaker 1: like an ancestor simulation. Or maybe the humans of the
Speaker 1: future are too moral to run an ancestor simulation, that
Speaker 1: the possibility that suffering could arise in the universe they create,
Speaker 1: like what we experience in our own universe now, is
Speaker 1: just too much of a moral gamble for their taste.
Speaker 1: In other words, they don't want the karmic mark against
Speaker 1: them for creating another universe where suffering lives. Or perhaps
Speaker 1: running ancestor simulations is just too hard, and of course
Speaker 1: it's always possible, they just don't feel like it. But
Speaker 1: take a closer look at this possibility. It shares the
Speaker 1: same fatal flaw with arguments that look to solve the
Speaker 1: family paradox. It presumes that not one, not one single
Speaker 1: future human decided to build a simulation of historic humans.
Speaker 1: Not a single person figured out a way to allocate
Speaker 1: some of that vast amount of computing power to simulate
Speaker 1: the universe and humanity in it. Not a single person
Speaker 1: came across a scientific study that would benefit from a
Speaker 1: model of human history, not a single person was curious
Speaker 1: enough of the quadrillions or possibly sex to sillions of
Speaker 1: humans left to come, who will populate a span of
Speaker 1: time lasting billions of years. Not a single one of
Speaker 1: them created an ancestor simulation. That's how it must be,
Speaker 1: because all it takes is one for one person in
Speaker 1: the future to run one single ancestor simulation, and the
Speaker 1: simulation argument is activated. But there's another possibility as well.
Speaker 1: Perhaps no ancestor simulations are run in the future because
Speaker 1: there are no humans around to run them. Here's where
Speaker 1: the simulation argument ties into existential risks if we're not
Speaker 1: simulated humans. In a very strange way, the simulation argument
Speaker 1: gives us a glimpse across the long expanse of time
Speaker 1: into our future. When we look ahead, it shows us
Speaker 1: that there are no humans around to run simulations of us.
Speaker 1: There are no humans who managed to spread from Earth
Speaker 1: and into the universe to put that cosmic endowment to use.
Speaker 1: It tells us that we will fail that in the future.
Speaker 1: We didn't make it through the Great Filter. But if
Speaker 1: you think we will make it through the Great Filter,
Speaker 1: and if you're not convinced that not a single one
Speaker 1: of our descendants will run a simulation, and of humanity,
Speaker 1: you're in luck. There's a third option that we are
Speaker 1: simulated humans living in a simulated universe. Yes, anybody can
Speaker 1: simply say that we are living in a simulation, just
Speaker 1: like anyone can say that we are living in what
Speaker 1: we call real reality. Neither one means anything. They're both
Speaker 1: just assertions. But the idea that we're living in a
Speaker 1: simulated reality actually has a leg up over the idea
Speaker 1: that we're living in real reality thanks to probability, lovable, unpredictable, programmable.
Speaker 1: It's the Sims. Back at the beginning of the year
Speaker 1: two thousand, the software company Maxis released The Sims, a
Speaker 1: life simulation game where you, the player, controls individual simulated people.
Speaker 1: The Sims. As one reviewer put it, as a celebration
Speaker 1: of the mundane Sims go about their lives, they go
Speaker 1: to work, they clean their toilets, and yes, they die.
Speaker 1: The Sims became an enormously popular game. Between two thousand
Speaker 1: and two thousand ten, a hundred and twenty five million
Speaker 1: copies of The SIMS and its successive editions were sold
Speaker 1: around the world. Each time one of those people brought
Speaker 1: their CD RAM home, loaded it into the tray, and
Speaker 1: booted up the software. A new iteration of the SIMS
Speaker 1: universe was created. It was the same universe. It followed
Speaker 1: the same rules, the same program, It followed the same
Speaker 1: physics and logic, and the SIMS all navigated their universe
Speaker 1: made up of the same set of possibilities, but each
Speaker 1: iteration was distinct and different. Each one was a discreet
Speaker 1: version of the SIMS universe, and we can expect something
Speaker 1: along the same lines with any simulations our ancestors might run.
Speaker 1: Whether it's a scientific model for an anthropological study of history,
Speaker 1: or whether it's the software of a popular game, whether
Speaker 1: it's a class project. Each time that simulation is run,
Speaker 1: a new iteration of our simulated human universe is created.
Speaker 1: Say that at some point in the future, again, it
Speaker 1: doesn't matter when, but at some point across the billions
Speaker 1: of years, among the quadrillions of people left to come,
Speaker 1: there's a ten year period where an ancestor simulation software
Speaker 1: that is equally as popular as the SIMS is created
Speaker 1: and sold. As all those future humans load their simulations,
Speaker 1: a new iteration of our simulated universe is born, each
Speaker 1: following the same guidelines, the same code, each taking radically
Speaker 1: different courses within the same set of prescribed rules, the
Speaker 1: same set of physics, as it were. If we're agreed
Speaker 1: that our descendants will run ancestor simulations of us, and
Speaker 1: that we don't have any frame of reference to distinguish
Speaker 1: the simulation from real reality, and in the future a
Speaker 1: hundred and twenty five million iterations of that simulated universe
Speaker 1: or run, then you and I and everyone alive in
Speaker 1: our universe has a one and one than twenty five
Speaker 1: million chants that we are actual humans, a one and
Speaker 1: a hundred and twenty five million chance that we are
Speaker 1: not simulated, Or, to put it somewhat less encouragingly, there
Speaker 1: is a ninety nine point chance that we are simulated
Speaker 1: humans living in an ancestor simulation being run in the future.
Speaker 1: Because there was one iteration of humans in real life,
Speaker 1: there is a chance that we are members of that
Speaker 1: genuine human race as we'd like to think of ourselves.
Speaker 1: But well, here's Nick Bostro, it's a little bit as
Speaker 1: if we ares s species. I thought we were Napoleon, right,
Speaker 1: So there are a lot of people who have thought
Speaker 1: that we're Napoleon. Has only been one actually Napoleon. There
Speaker 1: have been many more people that thought that we're Napoleon.
Speaker 1: Then actually we're in that pogum, And say, if you
Speaker 1: think you're kind of an emperor of world historic importance,
Speaker 1: you know, a chances are maybe you're actually a lunatic
Speaker 1: in and insane asylum. Because so many simulations are running
Speaker 1: in the future, given that we have no firm of
Speaker 1: reference to tell us any differences between our reality and
Speaker 1: basement reality, that utter lack of signs that we live
Speaker 1: in a dream, as Descartes suggested, the chances are vastly
Speaker 1: greater that we are simulated rather than real. There's just
Speaker 1: simply been more simulated humans than real ones, and being
Speaker 1: members of one group or the other, the chances state
Speaker 1: quite plainly that it's like clear we're members of the
Speaker 1: simulated group. You can mess with the numbers either way
Speaker 1: to make the chances go up or down. Say that
Speaker 1: ancestor simulation is way more popular than the sims ever was,
Speaker 1: and an equal amount of copies are sold each decade
Speaker 1: for a hundred years. That would mean that we had
Speaker 1: one chance in over a billion of being a human,
Speaker 1: and so on. Each new iteration of our simulated universe
Speaker 1: lowers the chances that we are real. But like I
Speaker 1: said before, even just one ancestor simulation run in the
Speaker 1: future activates the simulation argument eve. And if just once
Speaker 1: in the whole future history of the human race, only
Speaker 1: one iteration of our simulated universe is run, we still
Speaker 1: have even odds that were simulated. If we make it
Speaker 1: through the great filter, and our descendants run ancestor simulations
Speaker 1: of us, we have at best a fifty chance of
Speaker 1: being real humans. I should say that if it does
Speaker 1: turn out that we are simulated, our simulation could have
Speaker 1: been built by any number of things. It's possible the
Speaker 1: people who created us aren't future humans at all, but
Speaker 1: some other intelligent life entirely. It could be a race
Speaker 1: of Martian ancestors that real humans diverged from eons ago,
Speaker 1: an intelligent machine, super intelligent mice looking for the answer
Speaker 1: to the meaning of life. It's even possible that our
Speaker 1: universe follows a more basic set of physics than what
Speaker 1: governs the universe. Our universe is stimulated within. Perhaps there
Speaker 1: never was a one true race of real life humans,
Speaker 1: anymore than there was a real life race of sims.
Speaker 1: But the thing about the simulation argument is that it
Speaker 1: calls for the least amount of speculation, the least amount
Speaker 1: of unreality. For it to be right, all it requires
Speaker 1: is that our descendants will run simulations of humanity in
Speaker 1: the future. It's rather elegant in its simplicity. That's what
Speaker 1: makes it convincing. Even still, there are, as you may imagine,
Speaker 1: a number of objections to the simulation argument. Some people
Speaker 1: simply detest it on its face, dismissing it out of
Speaker 1: hand is nothing more than material for late night conversations
Speaker 1: in college dorms. But others engage with it seriously, and
Speaker 1: they raise legitimate issues. The thing is, it seems that
Speaker 1: every object action leveled against the simulation argument either imposes
Speaker 1: unnecessary time constraints or is just a simple failure of imagination.
Speaker 1: If this is the first you've heard of the simulation argument,
Speaker 1: at this point, you might be looking around you closely
Speaker 1: examining the edges of things, seeing if you can tell
Speaker 1: that the world is fake. Don't bother. The simulation argument
Speaker 1: doesn't change a single thing about our universe. The physics
Speaker 1: are the same as ever. Being persuaded that we live
Speaker 1: in a simulation doesn't unlock some greater understanding of our
Speaker 1: reality such that we can alter it in ways that
Speaker 1: we couldn't before. There's no pill to choose. There won't
Speaker 1: be any flying around or walking through walls, nor should
Speaker 1: your morality be altered. Your mother is just as real
Speaker 1: as she was before, and she would be just as
Speaker 1: disappointed as before if you decided to start a life
Speaker 1: of crime because we're simulated, So why does it matter.
Speaker 1: The court system is real too, and you would be
Speaker 1: imprisoned by it just as sure as ever. And when
Speaker 1: you explain to them that none of this is real,
Speaker 1: that they aren't real, the car you set fire too
Speaker 1: isn't real, that the whole universe isn't real, the mental
Speaker 1: health system will be just as happy as ever to
Speaker 1: lock you away in a padded room indefinitely, the walls
Speaker 1: of which you would find you were fully enabled to
Speaker 1: will yourself to walk through using your new found awareness
Speaker 1: of the simulated basis of our universe. Our universe is
Speaker 1: as real as it ever was. The only thing the
Speaker 1: simulation argument can change is your perspective. One common objection
Speaker 1: to the simulation argument kind of falls under this umbrella
Speaker 1: of misunderstanding. It goes something like this, how could a
Speaker 1: simulated banana or simulated apple, or a simulated cheeseburger possibly
Speaker 1: provide nutrients to us. How could it sustain and nourish us,
Speaker 1: alleviate our hunger, make us feel full. It's kind of
Speaker 1: like the hard problem of consciousness, the puzzle of how
Speaker 1: we get from neurons firing two subjective experience. Sure, you
Speaker 1: can simulate a banana, but you're simulating a banana. It's
Speaker 1: on a computer. And those of us who are looking
Speaker 1: at the banana, no, we are looking at a banana
Speaker 1: pictured on a computer. How can we account for the
Speaker 1: experience of interacting with a banana, holding one, peeling it,
Speaker 1: and needing it, of being allergic to it? How do
Speaker 1: we get from a simulated banana to the experience of
Speaker 1: a banana that is indistinguishable from reality. The answer is
Speaker 1: rather simple. We're not simulating that banana or cheeseburger or whatever,
Speaker 1: so it's not a simulation to us. It's made of
Speaker 1: the same stuff that we are. It's no more fake
Speaker 1: than you, You're no more real than it. We share
Speaker 1: the same reality. The banana isn't a simulated banana in
Speaker 1: our universe. It's just a banana, so it's subject to
Speaker 1: the same rules that we are on the quantum level.
Speaker 1: Those bananas are made up of energetic vibrations just like us.
Speaker 1: They form particles that are held together by the fundamental forces,
Speaker 1: just like us, and they form larger and more stable
Speaker 1: structures that increase in size and complexity up to the
Speaker 1: level of what we think of as a banana. And
Speaker 1: when we eat that particular package of energetic vibration, it
Speaker 1: interacts with our own energetic vibrations in such a way
Speaker 1: that we experience taste, in the sensation of deliciousness, We
Speaker 1: experience feeling full if we eat too many of them,
Speaker 1: and our bodies break them down into smaller parts, and
Speaker 1: we use those parts for energy, same as ever. Banana objections,
Speaker 1: as we'll call them, are rooted in the idea that
Speaker 1: we exist in some different reality from the banana. To
Speaker 1: be clear, the simulation argument does not suppose that there's
Speaker 1: some real version of you elsewhere. What we experience as
Speaker 1: our universe, bananas and all, is a simulation to someone else.
Speaker 1: To us, it is our full reality. So to answer
Speaker 1: the banana objection, the banana can satiate and sustain us
Speaker 1: because it's as real as we are. Other objections go
Speaker 1: a little deeper. How could we possibly simulate the universe
Speaker 1: on anything approaching a detail fine grained enough to be
Speaker 1: indistinguishable from the original. There are a couple of answers
Speaker 1: to this one. First, we can't. We don't have the
Speaker 1: computing power to faithfully render the universe in that detail.
Speaker 1: But in this objection we run into an unnecessary time constraint.
Speaker 1: While we can't faithfully reproduce the universe, there's a pretty
Speaker 1: good chance that our descendants will be able to. We
Speaker 1: Those of us alive today are already on track to
Speaker 1: doing this. For the last several years, humans have been
Speaker 1: able to produce accurate simulations of quarks and glue ones
Speaker 1: and the strong nuclear force that binds them together. These
Speaker 1: models are not infinitely press size, but they're faithful enough
Speaker 1: to reality that a simulated scientists living in the simulated
Speaker 1: universe where the protons exist would have no way to
Speaker 1: distinguish their unreality. They would just be protons that behaven
Speaker 1: appear exactly like any other protons. The models that we
Speaker 1: can produce today simulate an exceedingly tiny portion of our universe.
Speaker 1: They're on the scale of femptometers, about a quadrillionth of
Speaker 1: a meter. But the models show a proof of concept
Speaker 1: that simulating the universe is possible, and they also show
Speaker 1: that the human race already has a desire to simulate
Speaker 1: the universe. Already at this early stage in modeling the universe,
Speaker 1: we found that there are problems future humans will run
Speaker 1: into when it comes to scaling up those models. It's
Speaker 1: pretty obvious that modeling the entire universe would be a very,
Speaker 1: very difficult undertaking, but difficulties can be worked out over time.
Speaker 1: The problem comes when we reach impossibilities, and in two
Speaker 1: thousand seventeen, a pair of researchers from Oxford University found
Speaker 1: an impossibility that seems to show pretty conclusively that we
Speaker 1: do not live in a simulated universe. The researchers found
Speaker 1: that it would be physically impossible to simulate at least
Speaker 1: one aspect of the universe, something called the quantum Hall effect,
Speaker 1: which describes the way that electrons bounce between energy states
Speaker 1: called a quantum leap in the presence of a magnetic
Speaker 1: field and extremely low temperatures. It occupies a arcane a
Speaker 1: corner of particle physics as there is, But the point
Speaker 1: is the researchers found that to accurately simulate the effect.
Speaker 1: The computational power required doubles each time you add a
Speaker 1: new particle to the model, rather than increasing the power
Speaker 1: needed by one unit, it grows exponentially, so within just
Speaker 1: a few hundred particles, the operations per second required by
Speaker 1: a computer to run a simulation of the quantum Hall
Speaker 1: effect grows to a total beyond the number of atoms
Speaker 1: there are in the universe, around ten to the eighty
Speaker 1: second power. Not only is that number vastly more operations
Speaker 1: than our computers can perform today, this also presents a
Speaker 1: major technical issue. We need electrons to perform the computations
Speaker 1: that create the simulated model. In the first place, electrons
Speaker 1: are what we use to carry information in our computers,
Speaker 1: and as we simulate more and more particles subject to
Speaker 1: the quantum Hall effect, we will start to require a
Speaker 1: substantial portion of the electrons that are part of those
Speaker 1: ten to the eighty second power atoms in the universe.
Speaker 1: And as you may know, those electrons are otherwise occupied
Speaker 1: performing other functions like making up all the matter in
Speaker 1: the universe, which means that eventually it becomes physically impossible
Speaker 1: to simulate the quantum Hall effect and since we can
Speaker 1: observe the quantum Hall effect in our own universe, we
Speaker 1: can reason that our universe is not a simulation. But
Speaker 1: this presents a failure of imagination, not an impossibility. Indeed,
Speaker 1: the researchers who made the discovery noted that they're finding
Speaker 1: only showed that we couldn't possibly be simulated within a
Speaker 1: traditional computer, the type that we have available to us now,
Speaker 1: the kind that uses electrons. They also pointed out that
Speaker 1: we can probably safely presume that the humans of the
Speaker 1: future would be simulating us on better computers than what
Speaker 1: we're using today. I've said it before, and I'll say
Speaker 1: it again. If it turns out that the humans of
Speaker 1: the future don't have better computers than we have now,
Speaker 1: it would be one of the more surprising things in
Speaker 1: this entire series. And indeed, we are working on better
Speaker 1: computers already, specifically, quantum computers, the type of computer that
Speaker 1: processes information not gleaned from the movement of electrons, but
Speaker 1: instead from the interaction of elementary particles, which exponentially opens
Speaker 1: up a computer's capacity to perform calculations in a single
Speaker 1: second and meet lee transfers, rendering the quantum Hall effect
Speaker 1: and a simulation from the impossible column over to the
Speaker 1: column marked possible. We've already talked about that to accurately
Speaker 1: simulate a human or to require simulating a mind that
Speaker 1: is capable of subjective experience. If the hard problem of
Speaker 1: consciousness isn't actually a problem after all, then by creating
Speaker 1: an accurate model of all of the bits that make
Speaker 1: up a human mind, the neurons and synapses, the neurochemicals,
Speaker 1: we can imagine that they will produce subjective experience when
Speaker 1: they interact with the matter and energy that makes up
Speaker 1: the simulated universe. This is exactly the same concept as
Speaker 1: a post biological civilization that has shed their physical form
Speaker 1: and migrated onto computers. If you found the concept of
Speaker 1: a post biological future for humanity plausible, then you should
Speaker 1: have no trouble accepting the simulation argument. The only difference
Speaker 1: between the two is that, rather than us migrating onto
Speaker 1: computers ourselves, we will have always been there already. As
Speaker 1: Nick Bostrom points out in his paper on the simulation argument,
Speaker 1: the human brain can process about ten to the seventeenth
Speaker 1: power operations per second. If that's the amount of processing
Speaker 1: power it takes to experience subjective reality. Then that's about
Speaker 1: what we would expect it would take to simulate a
Speaker 1: human mind, and to run a simulation of all of
Speaker 1: human history would require that amount times around a hundred
Speaker 1: and seven billion, since that's the number of humans who
Speaker 1: have been born up to this point. Although we can't
Speaker 1: imagine that as humans die, the processing power required to
Speaker 1: produce their subjective experience would be freed up to power
Speaker 1: the minds of new humans as they're born. So perhaps
Speaker 1: all you'd ever need is enough processing power to simulate
Speaker 1: all of the minds of the humans who are alive
Speaker 1: at any given point, which means that to simulate a
Speaker 1: global population of ten bills people, you'd need a computer
Speaker 1: capable of processing ten to seven power operations per second.
Speaker 1: That's not including the processing power it would take to
Speaker 1: simulate the universe, which we could expect would expand the
Speaker 1: requirements to mind boggling numbers. There are surely a lot
Speaker 1: of corners future humans can cut to create a simulation.
Speaker 1: They wouldn't need to simulate the entire universe obviously, just
Speaker 1: what we can detect. Then it's possible they wouldn't need
Speaker 1: to simulate the universe at all. Rather, they could just
Speaker 1: create a program that stimulates our minds directly to experience
Speaker 1: the universe. Even with the shortcuts, though, there's still an
Speaker 1: enormous amount of ground to cover before we get to
Speaker 1: the point where we have the processing power of the
Speaker 1: magnitude required to simulate a human mind, let alone all
Speaker 1: seven and a half billion of us. Take this for example.
Speaker 1: Back in two thousand fourteen, the Fujitsu Corporation ran a
Speaker 1: test on its Fujitsu K, at the time, the fourth
Speaker 1: fastest supercomputer in the world, ranking that is no small feat.
Speaker 1: In the test, the Fujitsu engineers wanted to see how
Speaker 1: long it took their K computer to process one percent
Speaker 1: of the amount of information that a human brain can
Speaker 1: process in one second. The K managed to process that information,
Speaker 1: but rather than the hundredth of a second it would
Speaker 1: have taken a brain, it took the computer forty minutes
Speaker 1: to complete the task. And it's worth noting the K
Speaker 1: required twelve point seven megawatts of electricity throughout the forty
Speaker 1: minutes it was running this test, about the same amount
Speaker 1: of electricity needed to power the entire city of Sacramento, California.
Speaker 1: Considering the gap between where we are now and what's
Speaker 1: required to run a respectable ancestor simulation. It might start
Speaker 1: to seem that such simulations are indeed impossible but easy.
Speaker 1: There we're only running up against an unnecessary time constraint. Again,
Speaker 1: given enough time, it seems quite possible to build a
Speaker 1: computer that could run an accurate simulation. As Boston points out,
Speaker 1: a single one of those planet sized computers could perform
Speaker 1: ten to the forty second operations per second. To run
Speaker 1: an ancestor simulation would require just the slightest fraction of
Speaker 1: that computer's processing power, And we can imagine that in
Speaker 1: a far enough expanse into the future, if our descendants
Speaker 1: have one planet sized computer, they will eventually have a
Speaker 1: great many of them. And let's not forget we humans
Speaker 1: have a long standing tradition of advancing by leaps and
Speaker 1: bounds in computing. If you wanted to find the top
Speaker 1: of the line in supercomputers back in you needed to
Speaker 1: look no further than the Cray Too. Recently, scientists producing
Speaker 1: these simulations at NASA's Aims Research Center in Mountain View, California,
Speaker 1: began using a new supercomputer, the Cray Too. It was
Speaker 1: just a little smaller than the size of a BW
Speaker 1: beatles stood on its end, but the CRY two could
Speaker 1: perform two hundred and fifty million operations per second, an
Speaker 1: astounding amount. In just over thirty years later, Apple released
Speaker 1: a computer that could perform six hundred billion operations per second.
Speaker 1: Apple called There's the iPhone tent, which, by the way,
Speaker 1: is run by a machine learning algorithm capable of self improvement.
Speaker 1: We already share the planet with quantum computers, the very
Speaker 1: kind of computer that could simulate a universe to a
Speaker 1: detail down to the quantum grain. The ones we share
Speaker 1: the planet with today are exceedingly slow compared to our
Speaker 1: current traditional computers, but they are in the earliest stages
Speaker 1: of development. It was only in the eighties that physicists
Speaker 1: began designing quantum computers that could work in theory, and
Speaker 1: only in the nineties when the first quantum computers were built.
Speaker 1: We can imagine that if we continue to follow this arc,
Speaker 1: those primitive quantum computers of today will advance as well
Speaker 1: as our traditional ones have. We haven't even lived with
Speaker 1: traditional computers for a century, yet imagine what our quantum
Speaker 1: computers will be capable of a century from now. There are,
Speaker 1: to be sure, numerous other objections to the simulation argument,
Speaker 1: but most, if not all, have difficulty overcoming that non
Speaker 1: limitation of time. When we give our descendants the luxury
Speaker 1: of time, those people whose future lives we will save
Speaker 1: by taking on our existential risks become capable of anything
Speaker 1: that we can imagine and more, including simulating us. Back
Speaker 1: in two thousand twelve, a group of physicists from Bond
Speaker 1: University in Germany announced that they had figured out a
Speaker 1: way to test whether we live in a simulation. If
Speaker 1: our simulation is anything like the femtometer scale simulated models
Speaker 1: of protons that we can produce now, then that means
Speaker 1: it isn't an infinitely accurate copy of the real universe
Speaker 1: predicted by Einstein's theory of relativity. One of the things
Speaker 1: that relativity says is that the universe is built from
Speaker 1: a structure made up of the three spatial dimensions and
Speaker 1: time spacetime. Spacetime is the fabric of our universe, and
Speaker 1: it's contiguous, one giant universe sized unit. There's no gaps
Speaker 1: in it anywhere, no matter how far we zoom in.
Speaker 1: Remember when energy fields came up in the Physics episode
Speaker 1: and I mentioned that these energy fields are everywhere at
Speaker 1: every point in time and space. That's what that means.
Speaker 1: There's no place where those fields aren't because there's no
Speaker 1: gaps in spacetime. There's no place where space doesn't exist,
Speaker 1: just as there aren't any gaps in time where there's
Speaker 1: no time. It would take an enormous computer to render
Speaker 1: an infinitely accurate version of our universe, potentially one the
Speaker 1: exact size of the universe, and so we might guess
Speaker 1: that the designers of our simulation would be forced to
Speaker 1: make a version that's just slightly less accurate than the
Speaker 1: real thing, which would mean that the fabric of the
Speaker 1: simulated universe wouldn't be infinitely smooth. There would be gaps
Speaker 1: in its structure gept between the individual units that it's
Speaker 1: built from. If we could only zoom in close enough
Speaker 1: to examine it, we would find the fabric of our
Speaker 1: simulated universe was pixelated. But we can't zoom in that
Speaker 1: close to observe space time directly. So the Bond University
Speaker 1: researchers suggested a way that we could indirectly observe it
Speaker 1: by watching how these smallest bits of matter in the
Speaker 1: universe ultra high energy cosmic rays travel around space. Remember
Speaker 1: Cosmic rays are high energy particles most likely spit out
Speaker 1: from supernova that zip around our universe and collide with
Speaker 1: other particles and may or may not produce microscopic black
Speaker 1: holes when they do. They're one of the things that
Speaker 1: we model in particle colliders. If spacetime is contiguous in
Speaker 1: our universe, as we think it's supposed to be, then
Speaker 1: cosmic race should travel in every possible direction. Since there's
Speaker 1: no gaps in spacetime, there's nothing to direct their paths.
Speaker 1: There aren't any channels in the fabric of space for
Speaker 1: them to fall into and travel along. But if spacetime
Speaker 1: is pixelated, the very fabric of the universe would form
Speaker 1: an infinitismally fine grid. There would be tracks that the
Speaker 1: tiniest cosmic rays might travel along. So, say the Bond researchers,
Speaker 1: if we managed to observe that cosmic rays follow a
Speaker 1: grid pattern, or that they show a preference for traveling
Speaker 1: at angles rather than moving in every possible direction as
Speaker 1: they should, we might have a fairly good indication that
Speaker 1: what we're viewing as reality is actually a simulated version
Speaker 1: of it. Interestingly, the idea that spacetime is grainy rather
Speaker 1: than smooth is starting to gain traction among physicists. The
Speaker 1: absolutely smallest discrete measure of distance in the universe is
Speaker 1: called the plank length. Anything smaller than it, and physics
Speaker 1: just falls to pieces. It's difficult to get across how
Speaker 1: small a plank length is. It's about a hundred quintillion
Speaker 1: times smaller than a proton, which itself is about a
Speaker 1: hundred thousand times smaller than an atom. In fact, if
Speaker 1: we could zoom into the plank scale so that a
Speaker 1: plank length was the size of an atom, the atoms
Speaker 1: in the universe would be the size of galaxies. It's
Speaker 1: that small. Since spacetime is supposed to be infinitely smooth,
Speaker 1: it's weird that there's the smallest point beyond which physics
Speaker 1: is just meaningless. It's possible that our math is wrong,
Speaker 1: or that when we managed to marry relativity and the
Speaker 1: standard model into a theory of quantum gravity, we'll find
Speaker 1: that physics picks up again beyond the plank scale. But
Speaker 1: some quantum physicists are beginning to wonder if perhaps there
Speaker 1: is some non infinite bottom size to the fabric of
Speaker 1: space time, and that the plank length maybe it. Perhaps
Speaker 1: we're beginning to uncover the frame of reference they Carte
Speaker 1: longed for to distinguish between our reality and real reality.
Speaker 1: But even as we chip away at the nature of
Speaker 1: our own reality, if we find that we are indeed simulated,
Speaker 1: we run into an issue. We still don't know anything
Speaker 1: about the nature of real reality. All of our questions
Speaker 1: just get kicked up to the universe that's simulating us.
Speaker 1: There's a problem with that because we can't say for
Speaker 1: sure that the universe we are simulated within isn't simulated itself.
Speaker 1: So the problem can be kicked up indefinitely. Since in
Speaker 1: the simulation argument, the people who are simulating us are
Speaker 1: also humans themselves. They are, remember, the descendants of the
Speaker 1: people we are simulations of. The same staggering probabilities against
Speaker 1: us being real life humans applies to them as well.
Speaker 1: Just by their membership and the human race and the
Speaker 1: existence of ancestor simulations. The people who simulated us have
Speaker 1: that same ninety nine point chance of being simulated just
Speaker 1: because they are running the simulation of their ancestors doesn't
Speaker 1: identify them as members of the real human race. The
Speaker 1: simulation can run inside a simulation. When our descendants run
Speaker 1: ancestor simulations. In the future, there will be simulated versions
Speaker 1: of the universe existing within our own. But if we
Speaker 1: are simulated, then the simulations we run will be simulations
Speaker 1: within our simulation, and the same possibility applies to the
Speaker 1: people running our simulation, to their universe may be simulated
Speaker 1: as well. Perhaps it's an almost certainty that once a
Speaker 1: simulated group of humans reaches some specific point, they will
Speaker 1: begin to run ancestor simulations themselves, the ones that make
Speaker 1: it through the great filter at least, and so ancestor
Speaker 1: simulation spread in each direction from our own universe, simulations
Speaker 1: within simulations within simulations, kind of like how it looks
Speaker 1: inside an elevator that has mirrors on all sides. We
Speaker 1: ner what's called an infinite regress problem. We can figure
Speaker 1: out that our universe is simulated, but what does that
Speaker 1: tell us about the universe the people who are simulating
Speaker 1: us live in. Actually, this is familiar territory for physics.
Speaker 1: One implication of cosmology is that our universe is one
Speaker 1: bubble amid an infinite froth of bubbles, each their own universe.
Speaker 1: And since our universe is an isolated system, no matter
Speaker 1: or energy can leak out of it, and we presume
Speaker 1: the same about those other universes, which means that we
Speaker 1: can't glean any information about those other universes that we
Speaker 1: rub up against in the infinite froth, and we likely
Speaker 1: never will. And yet you would be hard pressed to
Speaker 1: find a physicist who suggested throwing in the towel on
Speaker 1: investigating our own universe when cosmology reached this conclusion. The
Speaker 1: same holds true for the idea that we're simulated. Not
Speaker 1: being able to know anything about the universe that simulated
Speaker 1: us doesn't mean there's nothing to be gained from investigating
Speaker 1: our own It's worth taking a step back here to
Speaker 1: look at the implications of what it means. When we
Speaker 1: start talking about who is simulating us, we're talking about
Speaker 1: someone who in some respect created us. Perhaps one of
Speaker 1: the touchiest aspects of the simulation argument is that it
Speaker 1: suggests a sort of techno creationism. Although it does fall
Speaker 1: under the umbrella of creationism, accepting the idea that we
Speaker 1: may be simulated does to require any form of supernatural
Speaker 1: or religious belief. If we're simulated, we can identify who
Speaker 1: created us. It's the descendants of the people who were
Speaker 1: simulations of future humans created us. But who exactly would
Speaker 1: the software developer who wrote the code that produced us
Speaker 1: qualify as our creator? Would the person who directly booted
Speaker 1: up the simulation we live in? Or what if our
Speaker 1: simulation is a scientific model, does our creator where a
Speaker 1: lab coat and our simulation is a digital Petrie dish
Speaker 1: of sorts? Or is our creator a far future teenager
Speaker 1: who created us for a class project. I should remind
Speaker 1: you that it's important to remember the simulation argument doesn't
Speaker 1: prove anything about our perceived reality. It gives no evidence
Speaker 1: one way or the other. It's a framework for viewing
Speaker 1: the nature of our universe, which means that, like any
Speaker 1: other argument, you can take or leave it. It is
Speaker 1: a matter of personal belief whether the idea of being
Speaker 1: created from a program written by future humans is more
Speaker 1: or less comforting than the idea that a supernatural deity
Speaker 1: created us, or that the world grew on the back
Speaker 1: of a turtle, or that we're the fluke result of
Speaker 1: an incomprehensible series of cause and effect stretching back nearly
Speaker 1: fourteen billion years. If we did one day discover that
Speaker 1: we are stimulated humans living in a simulated universe, that
Speaker 1: would we can imagine have enormous and sweeping effects on us.
Speaker 1: Even if you already believe that we were created, how
Speaker 1: would you feel to learn that your creator is only human,
Speaker 1: with all the same faults and flaws that you have.
Speaker 1: And if you don't believe today that we were created,
Speaker 1: that we are merely the result of some physical processes
Speaker 1: that can turn dead matter into cellular life, and that
Speaker 1: we were shaped by the forces of evolution, learning indisputably
Speaker 1: that we were indeed created, it would be a tough
Speaker 1: pill to swallow. But would those enormous and sweeping effects
Speaker 1: be all bad and would they be permanent? This is
Speaker 1: Ander Sandberg again. I do think that if we realize
Speaker 1: that the universe fundamentally work differently from how we used
Speaker 1: to believe it was, we would be shaking, But we
Speaker 1: would also get over it, just like we have gotten
Speaker 1: over and the hellyo some traces, and the evolution and
Speaker 1: the Freud and so on. Most people are way more
Speaker 1: resilient to upsets of the fundamental structure of the world
Speaker 1: than we give them credit for. We humans are really
Speaker 1: good at absorbing terrible news, whether it's a cancer diagnosis
Speaker 1: or learning that we're facing existential risks. There's a chance
Speaker 1: we will survive, there's a chance we won't. But do
Speaker 1: we simply lay down and die. Humans tend not to
Speaker 1: do that. Instead, we carry on. We seek out connections
Speaker 1: and support from other humans who are also carrying on,
Speaker 1: and we might expect the same would hold true should
Speaker 1: we learn that we're simulated. Even despite finding that we
Speaker 1: are the result of code, nothing about the meaning of
Speaker 1: our lives should necessarily be lost. Well where do we
Speaker 1: get a meaning in our own lives? And I would
Speaker 1: argue that we're actually creating it ourselves. Even if the
Speaker 1: universe was a class project to demonstrate the sociological and thing,
Speaker 1: that doesn't mean it's the meaning of our life to
Speaker 1: not behave socially, It's not like our loves and the
Speaker 1: emotions that will become meaningless, and we might still have
Speaker 1: a meaning that's very different from the reason the simulation exists.
Speaker 1: It will probably be tough to keep in mind, especially
Speaker 1: for the people who are alive at the time, when
Speaker 1: we learn our universe is simulated, But at bottom, really
Speaker 1: nothing much changes for us. Our understanding of our nature
Speaker 1: only deepens in a very direct way. Learning we are
Speaker 1: stimulated would focus our investigation into our universe it would
Speaker 1: certainly explain a lot. The Bond University researchers who came
Speaker 1: up with the cosmic ray grid test suggested that perhaps
Speaker 1: we'd find the reason the Higgs field is in in
Speaker 1: its lowest energy state is because of a rounding error
Speaker 1: and the computations that produce our simulation. Maybe the measurement
Speaker 1: problem that quantum particles seem to exist in all of
Speaker 1: the possible forms they can take at the same time
Speaker 1: is a shortcut to make rendering the universe more efficient.
Speaker 1: The fine tuning we see would certainly be explained. The
Speaker 1: parameters of the forces and energy that make up our
Speaker 1: universe would have to be the way they are because
Speaker 1: we could not be produced under other conditions. But that's correct,
Speaker 1: whether we're simulated or not. Finding we're simulated would identify
Speaker 1: computer code as the basis of those governing principles that
Speaker 1: we already take to be true, like a biogenesis and evolution.
Speaker 1: We wouldn't expect the understanding the truth of that would
Speaker 1: change how those processes function, but perhaps we could learn
Speaker 1: how to change them ourselves. Maybe learning we are simulated
Speaker 1: would free us to abandon the notion of fate and
Speaker 1: take control of how the universe operates to shape it
Speaker 1: more to our liking. After all, isn't that what the
Speaker 1: study of physics is? Taking control of the universe would
Speaker 1: also focus the moral responsibility that we have in making
Speaker 1: our universe a better place. Having the ability to reduce
Speaker 1: suffering wherever we found it, we would be morally obligated
Speaker 1: to do so. But then that's the case already as well.
Speaker 1: The difference is that we couldn't let ourselves off the
Speaker 1: hook by chalking that suffering up to inevitability like we
Speaker 1: do now. This is Seth show Stack, the senior astronomer
Speaker 1: at City who you met in the first episode on
Speaker 1: the Family Paradox. The question that I asked the Professor
Speaker 1: Bostrom that I think was most relevant to me was, Okay,
Speaker 1: if this is all a simulation, this conversation we're having,
Speaker 1: it's not real. It's just code. Right. If it's all
Speaker 1: just code, do I have to live a moral existence
Speaker 1: or kind just have fun? He thought it was better
Speaker 1: to live a moral existence, uh, you know, And I
Speaker 1: thought that that was kind of a testimony to how
Speaker 1: he really felt on the matter, that you know, you
Speaker 1: better act like it's real. The beautiful thing about the
Speaker 1: simulation argument is that it doesn't change anything, only our perspective.
Speaker 1: The world continues to operate in exactly the same way
Speaker 1: as before. It's just that some of the mystery is
Speaker 1: brushed away. Nothing about humanity changes, nor does anything about
Speaker 1: where we find ourselves in the position. Where as Toby
Speaker 1: Ord paraphrase Carl Sagan, we humans have grown powerful before
Speaker 1: we've grown wise, the existential risks we face remain as
Speaker 1: real as ever, and if we did find we are simulated,
Speaker 1: our existential risks would only sharpen, since we would learn
Speaker 1: of a new one that our simulation could be turned off,
Speaker 1: which I opposed, would qualify as a natural existential risk.
Speaker 1: Whether we arrived at this point where we have grown
Speaker 1: powerful before we've grown wise, by total fluke or by predetermination,
Speaker 1: whether we are members of the real human race or simulated,
Speaker 1: we are in the same unique and precarious position that
Speaker 1: we were in before. We are still entering the mouth
Speaker 1: of the great filter, and we are still at risk
Speaker 1: of our existence coming to a permanent end. If we
Speaker 1: fail to come together as a world and learn to
Speaker 1: use science to help us grow wiser faster, we will
Speaker 1: surely not survive. We will accidentally wipe ourselves out with
Speaker 1: our unwise power, and that will be the end of
Speaker 1: humans in our universe. Does it matter whether that universe
Speaker 1: arose from a big bang or from a system boot,
Speaker 1: Whether we are real or simulated, our reality is the same.